JP3400876B2 - Busbar phase converter structure - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a busbar phase conversion suitable for use as a termination box for connecting a ladder cable for connecting a transformer installed in a power plant and an auxiliary device such as a distribution cubicle. Regarding structure.

[0002]

2. Description of the Related Art For example, a 6900-volt three-phase electric circuit between a transformer such as an on-site transformer or a starting transformer of a power plant and a distribution cubicle which is a substation accessory is
Each phase is composed of a ladder cable consisting of cables attached on the ladder tray. In such an electric circuit, there is a case where the phase relationship between the one transformer and the auxiliary device connected to the transformer is deviated, and the positional relationship of the phases is interchanged. In such a case, the cables in which the positional relationship of the phases is exchanged can be twisted to match the phase relationship between the transformer and the accessory device.

However, from the viewpoint of maintenance and the like, it is desirable that such cables are arranged on the ladder tray in parallel with each other without causing entanglement with each other as much as possible. Therefore, when the cables are arranged in parallel without twisting each other, if the phases are different at both ends of the cable, the positional relationship of the phases is exchanged inside the junction box provided at the end of this cable. Is provided for the phase conversion.

FIG. 2 is an enlarged perspective view showing a part of a conventional phase converter. The three-phase conversion unit 1 used in the conventional junction box has the respective end portions 1a, 1b, 2a, 2
b, 3a, 3b, the ends of two in-phase cables are connected to each of the three U-shaped connection terminals 1U, 2V, 3
W, and three bus bars 4W, 5V, 6U which are arranged in alignment with each other from the back surface of each connection terminal,
It is provided with a connecting terminal and three connecting fittings 7U, 7V, 7W arranged between the busbars facing the connecting terminal.

Of the three bus bars 4W, 5V, 6U, the bus bar 5V located in the middle has three connection terminals 1U, 2
The connection terminal 2V located in the middle of V and 3W is connected in the same phase. From this, these members 2V
And a connecting terminal 2 as a connecting metal 7V for connecting 5V and
For V, a straight metal fitting 7V whose one end is connected via a connecting portion 2V-1 welded to the back surface thereof is used. However, the connection terminals 1U and 3W located on both sides of each of the members 2V and 5V and the bus bars 4W and 6U facing the connection terminals have a relationship in which their phases are interchanged.

For this reason, the cross-connecting metal fitting 7U arranged between each of the members 1U and 4W, 3W and 6U.
And 7W for connecting members in phase with each other,
They are arranged in a connection relationship that intersects with each other. Moreover, in order to ensure electrical insulation between the phases, the cross-connecting metal fitting 7U
2 and 7W, a crank-shaped plate member is used when viewed from above in the perspective view of FIG. 2, and are connected to the connection terminal by welding, and the connecting portions 1U-1 and 3W extend longer than the connecting portion 2V-1. It is connected to the corresponding connection terminals 1U and 3W via -1.

By the way, such a connecting portion is 3000
Since a large current of amperes flows, it is not possible to use, as the crank-shaped cross-connecting metal fittings 7U and 7W, a thin sheet metal that can be punched. Therefore, the cross connection fittings 7U and 7W are formed by integrally joining the plate members by welding so that the plurality of linear plate members form a crank shape as a whole.

[0008]

Therefore, in the conventional structure of the phase converting portion, the manufacturing process of the connecting portion becomes complicated, and therefore it is desired to develop the structure of the phase converting portion having a simpler structure. It was Further, each of the connecting fittings 7U to 7W is connected by a bolt-nut assembly at each end, but the fact that there are many connecting portions by bolts and nuts in such a large current passage means that it is manufactured. In addition to simplifying the worker,
It was not preferable in terms of electrical maintenance and safety.

[0009]

DISCLOSURE OF THE INVENTION According to the present invention, three-phase plate-like connecting terminals are arranged with their respective plate surfaces positioned parallel to one surface, and the central connecting terminal is parallel to the surface. A plate-like straight connecting portion that has a flat plate surface and a plate-shaped central bus bar that has a plate surface that extends integrally from the straight connecting portion and that is formed by twisting and that is orthogonal to the surface, and that is parallel to the surface. A plate-shaped cross-connecting portion having a plate surface and extending from a connecting terminal on one side across a straight connecting portion on one surface side, and a plate surface parallel to the surface, and a connecting terminal on the other side. From the other plate-shaped cross-connecting portion that extends across the straight-line connecting portion on the opposite surface side, and a pair of double-sided busbars that are joined to each bent end of both cross-connecting portions with a plate surface orthogonal to the surface And are included.

[0010]

In the structure of the busbar phase converter of the present invention, the central direct
The board surface of the line connection part and the cross connection part of the two cross connection parts are parallel to each other.
It It is possible to form the cross-connect unit by bending without the use of a conventional such welding in the manufacture of cross-connect unit itself. As a result, the number of connection parts in the phase conversion part can be reduced.

[0011]

The present invention will be described in detail below with reference to the illustrated embodiments. FIG. 1 is an enlarged perspective view showing a busbar phase converter 10 according to the present invention. Prior to this, a cable termination junction box 12 incorporating the busbar phase converter 10 is shown.
The description will proceed with reference to FIG. 3 and FIG.

3 and 4 are a plan view and a front view, respectively, showing the inside of the cable terminating junction box 12 according to the present invention by breaking the casing 14. As shown in FIG. Although not shown, the cable termination junction box 12 according to the present invention is one end of a cable group for connecting a transformer in a substation and an accessory device such as a distribution cubicle connected to the transformer. It is provided in. In the illustrated example, the cable termination junction box 12 is provided at the tip of a cable group extending from an accessory, and includes a rectangular casing 14 as a whole. Inside the casing 14, there are provided a cable connecting portion 18 to which the cable group 16 extending from the accessory device is connected, and a socket portion 20 to be connected to each connecting terminal of the transformer.

Casing 1 provided with socket 20
A vibration absorbing member 22 for abutting the connection surface of the transformer provided with the connection terminal of the transformer to cut off the vibration from the transformer is provided at one end of 4. Further, the socket portion 20 is provided with connection terminals 24 (U, V, W) and neutral connection terminals 26 which are connected to the terminals of the U, V, W phases of the transformer. Each connection terminal 24 and 2
6 is a braided flexible conductor 28 (U, V, W) and 30
Are connected to one end of each. Each flexible conductor 28
The other ends of 30 and 30 are connected to respective one ends of connection conductors 34 (U, V, W) and 36 which are respectively held by the insulating support 32 and extend toward the cable connecting portion 18.

At the other end of the casing 14, a cable group extending from the above-mentioned auxiliary equipment is taken in, and this cable group is composed of two cables 38 (U, U, provided for each phase).
V, W) and a single neutral wire cable 40. Connection plates 42 (U, V, W) and 4 for connection are provided at the respective tips of the two-strand cable 38 and the neutral cable 40.
4 is compression connected. As shown in FIG.
The connecting plate 44 at the tip of the neutral cable 40 is connected to the insulating support 4 via a fastener 46 such as a bolt and nut assembly.
8 is connected to a terminal board 50 supported by The terminal board 50 extends linearly toward the neutral connection conductor 36, and is connected to the neutral connection conductor 36 via a joint plate 52 and fasteners such as bolts and nuts (not shown). .

However, the three-phase connecting conductors 34 (U, V, W) of the socket portion 20 on the transformer side are U, V, W when viewed from the side remote from the neutral connecting conductor 36 in FIG. The two cables 38 extending from the accessory side are arranged in the order of, but when viewed from the side far from the neutral cable 40,
They are arranged in the order W, V, U. Therefore, if each of the cables 38 (U, V, W) is linearly extended and connected to the opposing connection conductors 34 (U, V, W), the U phase and the W phase are connected to each other. become.

In order to achieve the matching of the phases,
Each of the two cables 38 and the connecting conductors 3 connected thereto
4, the converter structure 10 according to the present invention is applied. As shown in FIG. 1, the conversion portion structure 10 has, on both ends, two cables 38 each of which is an electric conductor.
(U, V, W, see FIG. 3) and three connection terminals 54 (U, V, W) each having a U-shape in which connection ends 54a, 54b are formed. One end is arranged to face the terminal, and the connecting plate 56 is provided at the opposite end.
(U, V, W, see FIG. 3) through corresponding connection conductor 3
Bus bar 58 (U, V, W) connected to 4 (U, V, W)
W) and. In the illustrated example, each bus bar 58 (U,
V, W) are vertically divided into two parts by a parting line along the longitudinal direction, and each of them is a joint plate 56 (U, V, W), and is divided into upper and lower parts by a bolt nut assembly 60 (see FIGS. 3 and 4). Are joined together.

The bus bars 58 (U, V, W) arranged in parallel at a distance from each other are, as clearly shown in FIG. 1, along the arrangement direction coinciding with the width direction of the distance.
The connection terminals 54, which are located in the order of U, V, and W, but which face each bus bar, are
They are located in the order of V and U. Therefore, both V and W phases on both sides of the central U phase are exchanged.

In order to exchange the phases, the rear surface of the U-shaped connection terminals 54 (U, W) located on both sides, that is, the surface facing the bus bar 58, is shown in FIG. The extending portions 60 (U, W) extending toward the bus bars 58 are formed from the portions located in the opposite directions when viewed in the vertical direction.

The U-phase connection terminal 54U has an extension portion 60U formed on the upper portion thereof, and the W-phase connection terminal 54W has an extension portion 60W formed on the lower portion thereof. By changing the relationship in the vertical direction, the extension portion 60U can be formed below the connection terminal 54U, and the extension portion 60W can be formed above the connection terminal 54W. Further, in the illustrated example, each connection terminal is composed of a pair of metal plates, and each extension portion 60 is integrally formed by each metal plate.
Instead of this, the extension parts 60 (U, W) can be integrally formed by separate members by welding or the like. However, in the passage of a high voltage and a large current of several thousand volts and several thousand amperes, it is desirable to have a configuration in which the number of connecting portions is reduced as shown in the figure because of problems such as maintenance and management.

Each extension portion 60 of the connection terminal 54 (U, W)
(U, W) and bus bar 58 (U, W in phase with this extension)
W) is provided with cross-connecting fittings 62 each having a long side portion 62A and a short side portion 62B formed by bending the long side portion 62A at a right angle. In the illustrated example, each of the cross connection fittings 62 is also composed of two metal plates. Each of the cross-connecting fittings 62 is arranged along the lateral direction in which the long side portion 62A crosses the bus bar 58, that is, the lateral direction that is the bus bar arranging direction, and at the tip edge of the long side portion 62A, the side of the corresponding extending portion 60. It is welded to the part. Further, the short side portion 62B of each cross connecting fitting 62 is welded to the corresponding bus bar 58 at the tip thereof.

A fastener such as a bolt-nut assembly can be used to connect the cross connection fitting 62 and the connection terminal 54 or the bus bar 58. However, when such a fastener is used, it is necessary to perform silver plating on each connection surface, and relatively frequent maintenance management is required to check the looseness of the fastener, etc. As shown, welding is preferred.

By connecting both the cross connection fittings 62, V
The connection terminals 54 (U, W) and the bus bars 58 (U, W) located on both sides of the phase are connected with the phases aligned. As shown in FIG. 5, the central bus bar 58V has its upper and lower divided portions twisted in the same direction or in opposite directions in the vicinity of the tip end portion thereof, and each tip end portion constitutes the connection terminal 54V. So that it is bent. With such a configuration, the number of connecting portions can be reduced.

In the cable termination junction box 12 according to the present invention, as described above, the cross connection fitting 62 of the busbar phase conversion portion 10 changes the positional relationship of the phases. for that reason,
Even if the positional relationship of the phases of the cable group provided at the end portion of the cable terminating junction box 12 and the cable group connected to the cable terminating box 12 is different, twisting is applied to both of the cable groups, and the cable groups are arranged in parallel. You can connect with.

Further, in the cable terminating connection box 12, this can be obtained by simple bending without using welding for forming the cross-connecting metal fitting 62 itself of the busbar phase converting portion 10 for converting the phase. As a result, the structure of the phase conversion portion can be simplified, the number of connecting portions such as welded portions can be reduced, and electrical safety and reliability can be improved.

In the above description, an example in which the present invention is applied to a cable termination junction box has been described, but the present invention is not limited to this, and the dislocation portion provided for the purpose of equalizing the impedance in the busbar electric circuit is not limited to this. It can be applied to the phase conversion unit.

[0026]

As described above, in the busbar phase conversion portion structure of the present invention, the cross-connecting metal fitting can be formed by bending without using conventional welding for manufacturing the cross-connecting metal fitting itself. Therefore, it is possible to reduce the number of connecting portions in the phase conversion unit. Therefore, the manufacturing process can be simplified, the manufacturing cost can be reduced, and the number of connecting portions is small, which is extremely advantageous in terms of maintenance and management.

[Brief description of drawings]

FIG. 1 is an enlarged perspective view showing a Busbar phase conversion unit according to the present invention.

FIG. 2 is an enlarged perspective view showing a conventional Busbar phase conversion unit.

FIG. 3 is a plan view showing an internal structure of a cable termination junction box provided with a busbar phase converter according to the present invention, with a casing cut away.

FIG. 4 is a front view showing the internal structure of the cable termination junction box provided with the busbar phase conversion unit according to the present invention by cutting away the casing.

FIG. 5 is an enlarged partial perspective view of the busbar phase conversion unit according to the present invention.

[Explanation of symbols]

10 Busbar phase converter 38 (U, V, W) electrical conductor 54 (U, V, W) connection terminals 58 (U, V, W) Bus bar 60 (U, W) extension part 62 cross connection fittings 62A long side 62B Short side

Claims (2)

(57) [Claims] 1. A three-phase plate-like connection terminal arranged with its plate surfaces positioned parallel to one surface, and a plate surface parallel to the surface from the central connection terminal. A plate-like straight connecting portion, a plate-like central bus bar having a plate surface extending integrally from the straight connecting portion and twisted to have a plate surface orthogonal to the surface, and a plate surface parallel to the surface. Having one plate-shaped cross-connecting portion extending from the connecting terminal on one side across the linear connecting portion on one surface side, and having a plate surface parallel to the surface, the connection on the other side The other plate-shaped cross-connecting portion that extends from the terminal across the straight-line connecting portion on the opposite surface side, and is joined to each bent end of both the cross-connecting portions with a plate surface orthogonal to the surface. A busbar phase conversion unit structure comprising: a pair of busbars on both sides. 2. The busbar phase conversion part structure according to claim 1 , wherein the busbars on both sides are joined to the cross connection part by welding.